With concern increasing in the U.S. to understand how to decrease the burden of disability associated with aging, we have been conducting a study to define older women at risk of disability and the causes of disablement. This study is conducted with support of space and personnel from the OPD-GCRC and through an investigator-initiated R01 from the National Institute on Aging entitled "Risk Factors for Physical Disability in Aging Women". The study, referred to as the Women's Health and Aging Study 11 (WHAS 11), is a prospective, observational study of a cohort of 436 women 70-79 years of age at baseline, to determine the characteristics of early functional decline, termed "preclinical disability", the risk factors and underlying causes of preclinical disability and progression to disability and dependency, and whether early decrements in physical functioning are predictive of future disability. Currently in its third year, WHAS 11 is being conducted in the Johns Hopkins Outpatient Department General Clinical Research Center (OPD- GCRC), within the Functional Status Laboratory located there. Because the WHAS II examination is centered in the OPD-GCRC, it has been possible to successfully conduct this complex study with otherwise limited funding. The OPD-GCRC permits muIti-disciplinary evolutions in sequential examination rooms with the support of trained OPD-GCRC research assistants and medical personnel. The Functional Status Laboratory in the OPD-GCRC has evaluated participants in this study for their second follow-up examination (completed 9/97) and begun the third follow-up examination during this period, seeing up to 3 study participants per testing day for a 4-5 hour examination. The examination operates smoothly, and particpants report they are highly satisfied with the experience. The evaluation includes the following: self report of physical functioning; performance-based measures of funciton; and standardized evaluation of diseases and physiologic changes, including spirometry, ankle-arm blood pressure, and graded exercise testing. In, addition, hypothesized modifiers of the relationship between disease and disability are assessed, including use ofcompensatory strategies, cognitive impairment, psychosocial functioning, social supports, and the individual's home environment.